It is proposed to extend our studies in the following two areas: 1. Canine cystinuria: We intend to contunue our investigation into the genetics of this disease. Studies on the renal lesion (and possible gut defect) are being extended. 2. Microbial transport of sugars: We purpose to study the role of protons in the membrane transport of galactosides in both Streptococcus lactis and Escherichia coli.